In the electric cleaning apparatus, a torque of a drive shaft is often reliably transmitted to a head for cleaning by means of an interaction between the drive shaft and a coupling structure, and the torque transmission is maintained under load. In addition, the interaction between the drive shaft and the coupling structure must ensure keeping the head on the drive shaft during the operation of the cleaning appliance, and allowing a user to conveniently remove the head from the drive shaft when the cleaning apparatus is not operated.
For example, the invention patent with the authorization announcement number CN101902986 B discloses a brush head/handle interface for an electric toothbrush, comprising: a brush head assembly having a brush member at one end thereof for cleaning teeth; a drive shaft extending from a handle portion of the toothbrush and driven to oscillates through a selected rotational angle, the drive shaft having one or more contact regions in which are located interface surfaces; a coupling member positioned at the other end of the brush head assembly and having a body portion, wherein the coupling member includes one or more interface portions which come into physical contact with said interface surfaces of the drive shaft when the drive shaft is inserted into the coupling member; and a spring member positioned around a part of the body portion so as to exert a sufficient force on the body portion and the coupling member large so that the physical contact between said interface portion or portions of the coupling member and said one or more contact regions of the drive shaft is sufficient to maintain actual retention of the brush head assembly on the drive shaft during operation of the toothbrush, while permitting a user to remove the brush head assembly from the drive shaft when the toothbrush is not operating.